Switching device with improved tablet actuator means

ABSTRACT

The switching device of a tablet type comprises a plurality of tablets each having bosses formed integrally on the surfaces of its sidewalls coaxially with bores formed in the tablets to receive an axis. The tablets are arranged on a base by passing the axis through said bores in such a manner that the bosses formed on two adjacent tablets face each other.

United States Patent lnventor Junji Ohno Hamamatsu-shi, Japan Appl. No. 802,368

Filed Feb. 27, 1969 Patented May 4, 1971 Assignee Nippon Gakki Seizo Kabushiki Kaisha Hamamatsu-shi, Japan Priority Apr. 13, 1968, Apr. 17, 1968, Apr. 19,

1968 Japan 43/29886, 43/30983 and 43/31689 SWITCHING DEVICE WITH IMPROVED TABLET ACTUATOR MEANS 9 Claims, 4 Drawing Figs.

US. Cl 200/1, 200/6, 200/172, 84/101 Int. Cl HOlh 9/00 Field of Search 200/1, 1

(A), 5, 5 (A), 5 (E), 6, 169, 172, 172 (A); 84/1.01

References Cited UNITED STATES PATENTS 3/1957 Bissonette et a1 200/1(A)X 11/1964 Thomas et al. 84/1.01 5/ l 966 Sorensen 200/172X 5/1967 Schwartz et al.. 200/6(B3 )X 12/1969 Maire 200/1(A)X Primary Examiner-Robert K. Schaefer Assistant Examiner-.1. R. Scott Altorney-lrving M. Weiner ABSTRACT: The switching device of a tablet type comprises a plurality of tablets each having bosses formed integrally on the surfaces of its sidewalls coaxially with bores formed in the tablets to receive an axis. The tablets are arranged on a base by passing the axis through said bores in such a manner that the bosses formed on two adjacent tablets face each other.

mmm 3576.958

FIG. 3

SWITCHING DEVICE WITH IMPROVED TABLET ACTUATOR MEANS This invention relates to a switching device of a tablet type placed on the operation board, for example, of an electronic organ.

An electronic organ generally employs a number of switches, particularly those of a tablet type, which are provided sideward of the keyboard surface to effect switching of a tone and sound effects. The provision of a number of independent switches in side-byside relationship requires a number of parts for mounting of the switches, which is not economical.

An object of this invention is to provide a switching device having such an arrangement that a plurality of tablet-type switches are disposed in parallel.

Another object of this invention is to provide a switching devicein which a contract means is arranged such that spring plate members are penetrated through sidewalls of a supporting frame, whereby assembling of the device is simple and easy.

The invention is now described in conjunction with a preferred embodiment with reference to the accompanying drawing, in which:

FIG. 1 is a perspective view embodying the switching device of this invention;

FIG. 2 is a cross section taken along the line [H1 in FIG. I; FIG. 3 is a cross section taken along the line Ill-Ill in FIG. 1 showing a tablet in its operative position; and

FIG. 4 is an exploded perspective view, on an enlarged scale, of a contact means of FIG. 3.

In' FIG. 1, the reference numeral generally designates a switching device comprising, as main component elements, a substantially horizontal base 11, a plurality of tablets I2 pivotally mounted on the base 11, and a contact means 13 (in FIG. 3) having a-plurality of contacts which engage and disengage each other by the operation of each of the tablets 12.

A plurality of projections 14 which correspond in number and inposition to the tablet 12 are serially formed on one surface of the base 11. As best shown in FIG. 2, each projection 14 may be formed in such a manner that the base 11 is cut and that such a cut portion is raised and positioned substantially at right angles with the plane of the base so that each projection has substantially an inverted letter U-shaped configuration. A bore 140 is formed in the upper portion of each of the projections in alignment with each other so that a rod-shaped axis 15 is received by the bores 14a in parallel with the surface of the base 1 1.

Each tablet 12 has a substantially rectangular box shape and an opening in the bottom portion. End walls 12a and 12b of the tablet have slightly curved surfaces. As shown in FIG. 3, an actuator plate 16 projects downwardly from the inner surface of each tablet 12 at a portion closer to the contact means 13 and is formed integrally therewith. Bores 17 are formed in sidewalls 12c and 12d of said tablet in alignment with each other, and bosses 18 are formed integrally on the outer surface of said sidewalls 12c and 12d in such a manner that said bores 17 are open therethrough. The sidewalls 12c and 12d of each tablet 12 are cut slopewise as at 12c at the bottom front end of the tablet so that the width of each sidewall is increased toward the rear. end of the tablet. When the tablets 12 are supported by the'axis 15 passing through the bores 17, each tablet is rotatable around the axis 15 from its normal horizontal position with respect to the base 11 to a position where said cut portion 12c is horizontal. This will be described later in detail.

As shown in FIG. 2, the tablets 12 (four tablets are shown only for the purpose of illustration) are so arranged that when the axis 15 is passed through the bores 17 via the bores formed in the projections 14 the outer surfaces of the bosses between two adjacent tablets engage each other, and that the tablets 12 angularly rotatable around the axis independently each from the other. The bosses 18 thus provide spacings between two adjacent sidewalls of the tablets. Between the inner wall surfaces of two tablets positioned at both ends of a series of the tablet arrangement and corresponding two projections are respectively inserted spacers 19 made, for example, of felt.

The ends of the axis 15 are secured by stopper rings 20 so that the movement of the tablets 12 in the longitudinal direction of the axis can be avoided.

As shown in FIG. 3, rectangular openings 21 corresponding in number to the tablets 12 are formed in the base 11 at positions closer to the rear ends of the tablets than said projections 14. The lower ends of the operation plates 16 formed integrally with the respective tablets extend through said rectangular openings 21. Cushion pieces 22 are mounted on the base 11 at positions respectively corresponding to the bottoms of the front and rear end walls of the tablets in parallel relationship with the axis 15, as depicted in FIG. I. This cushion can prevent foreign matter incoming from a spacing between the base and the front or rear end (as the case may be) of the tablet 12 from being introduced through said spacing into the chamber of tablet.

The reference numeral 23 represents sheet springs for keeping the respective tablets in either of the operative positions, each said sheet spring having a letter S-shaped forward end and a lower end secured to the base 11. Each tablet has a laterally extending pin 24 on its inner sidewalls. When the tablet 12 is pushed downwardly at its front end, said pin 24 slides downwardly along the surface of the sheet spring 23 against its spring action and stays at the dent portion of the S- shaped part of the sheet spring 23, thus permitting the tablet 12 to stay at its operative rotated position.

On the bottom surface of the base 11 is mounted the contact means 13 operated by the actuator plates 16 of the tablets 12 as already mentioned. The arrangement of the contact means 13 will be described with particular reference to FIG. 4. The reference 25 indicates a frame of a rectangular hollow columnar configuration, or of a tubular spacer and mounting member, having open ends, and which is made of an insulating material. A pair of recesses 26 are formed in the edges of the upper open end of the frame 25 at intermediate points of the opposing shorter sides thereof, and a pair of registering projections 27 are extended from the corresponding edges of the lower open end. In the sidewalls 25a and 25b which define the longer sides of the frame 25 are formed a plurality of groups of slits 28. In the FIG., each group consists of three rectangular slits formed vertically spacedly in the sidewalls 25a and 25b.

In practice, however, these slits 28 forming a group may be interconnected to form a single opening having notches. A long movable spring or resilient plate or switching blade 30 is securedly inserted through the intermediate slits in such a manner as to bridge the frame 25, while a pair of short stationary spring plates 29 are similarly inserted through the upper slits and the lower slits, respectively, and facing to the movable spring plate 30 with spacings therebetween. On the upper surface and the corresponding lower surface of the movable spring plate 30 are mounted contacts 31. Contacts 32 are respectively formed on each surface of the stationary spring plates 29 so as to correspond with said contacts 31. Although only two groups of slits and associated spring plates are illustrated in FIG. 4, it should be understood that two groups or slits corresponding to one tablet.

The width of each of the spring plates 29 and 30 is reduced within the frame 25. Namely, each spring plate is provided with opposite acute recesses in its edges or semicircularly cut from both sides to form narrow portions 29a and 30a, so that a circular opening is formed between two adjacent groups of spring plates. The reference numeral 33 indicates a cover for closing the upper open end of the frame 25, said cover comprising a cover plate 33a, a detachable locator or stop member in the form of a hollow cylindrical member 33b disposed on the bottom central surface of said cover plate 33a, and a pair of registering projections 34 integrally formed on the bottom surface of the cover plate 33a. The stop member 33b engages the arcuate edges of the spring plates which edges function as abutments so as to hold the plates against movement lengthwise. A female screw 35 is threaded in the innersurface of the hollow cylindrical member 33b at the upper and lower defined by the narrow portions of two adjacent groups of 5 spring plates, whereby the spring plates are rigidly secured in position. The contact means 13 thus formed is secured to the base 11 by means of a bolt 36 which threadably engages the partly threaded hollow cylindrical member 33b, as shown in FIG. 3. Under this condition, the forward end of the movable spring plates 30 are in face-to-face contact with the bottom end of the corresponding operation plate 16 of the tablet 12. A cover plate 37 of substantially a boxlike configuration is provided to cover the entire contact means 13. The cover plate 37 has recesses (not shown) which register with the registering projections mounted on the frame 25 as is secured to the contact means 13 by a bolt 38 which also threadably engages the inner threaded surface of the hollow cylindrical member 33b.

The switching operation of the device will now be described. As shown in FIG. 3, when the forward end of the tablet 12 is pushed down, the tablet rotates around the axis causing theoperation plate 16 to elevate upwardly, whereby the movable spring plates 30 urge or flex upwardly to engage the upper stationary spring plates 29 at the contacts formed on the respective surfaces. For this purpose, it should be understood that the movable spring plates 30 is biased tending to move upwardly at their forward portions. When the tablet 12 is returned to its original nonoperative position as indicated by broken lines, the operation plate 16 presses the movable spring plates 30 downwardly causing said movable spring plates to engage the lower stationary spring plates 29 via the contacts formed on the respective surfaces. The flow of an electrical current is thus switched between one movable spring plate 30 and a pair of corresponding stationary spring plates 29. Since the operation plate 16 of the tablet 12 contacts either the forward end or the rear end of the rectangular opening 21 formed in the base 111, it is possible to prevent foreign matter incoming from a spacing between the base and the front or rear end (as the case may be) of the tablet 12 from being introduced through said rectangular opening 21 into the contact means 13 housed in the cover plate 37. For this purpose, the width of the actuator plate should be such that the width of the rectangular opening 21 formed in the base 11 is covered substantially.

In the embodiment shown, each tablet 12 is provided with a pair of bosses on its sidewalls to provide a spacing between two adjacent tablets. It is understood that bosses may be formed only on one side of the respective tablets to provide an equivalent effect.

lclaim:

l. A switching device of a tablet type comprising a base (11) having a plurality of projections (14), an axis (15) penetrating through said projections (14) and secured thereby, a plurality of tablets mounted on said base (11) in parallel relationship with each other and each having bores (17) formed in opposing sidewalls thereof and at least one boss (18) formed on the outer surface thereof in coaxial relation with said bores to provide a spacing between two adjacent tablets, operation plates each projecting integrally from the lower surface of each said tablet, and a contract means (13) including spring plates having contacts formed thereon, said contacts being switched by each of said operation plates.

2. A switching device of a tablet type comprising a base, a tablet pivotally mounted on said base, an actuator projecting .trom said tablet, a frame of electrically insulating material having a rectangular hollow columnar configuration with open ends and opposite sidewalls, said sidewalls having, respectively, pairs of groups of slits perforated therein which slits are formed into elongated shapes each extending horizontally and are arranged vertically with respect to each group, a cover having a plate member closing one of said open ends and an interpally-threaded hollow cylindrical member disposed substantlally on the central part of said plate member, a pair of groups of spring contact plate members operated by said actuator and inserted in said groups of slits in a manner to bridge said opposite sidewalls, the portions of said spring contact plate members which are positioned in said hollow frame being cut off at both side edges thereof to form narrow portions so that a substantially circular opening is formed between said pair of groups of spring contact plate members, the hollow cylindrical member being inserted in said substantially circular opening, a cover plate covering said frame, and two bolts threadably engaged with said internally-threaded hollow cylindrical member, one of said bolts securing the frame to the base and the other of said bolts securing the cover plate to the frame.

3. A switch device as claimed in claim 2, wherein said open end closed by said plate member has recesses formed therein, and said plate member has projections formed integrally thereof, said projections engaging said recesses.

4. The switching device as claimed in claim 2, in which said contact means comprises a supporting frame (25) having a closed cross section and including a plurality of pairs of slits (28) formed in two opposing sidewalls thereof, a plurality of groups of spring plates corresponding in number to said tablets, each group including a pair of stationary spring plates (29) and a movable spring plate (30), which respectively penetrate through corresponding pairs of slits in a manner to bridge said opposing sidewalls of said supporting frame.

5. The switching device as claimed in claim 4, in which both of said stationary spring plates and said movable spring plates are disposed in parallel with said supporting frame and have narrow portions (29a), (30a) formed at side edges thereof within said supporting frame, said narrow portions defining openings between two adjacent groups of slits, and further comprising cylindrical members each inserted into each of said openings, whereby the spring plates are prevented from slipping out of position from said supporting frame.

6. A switching device comprising a horizontal base (11), a tubular mounting member (25) having one end disposed toward the underside of said base, two pairs of elongate laterally positioned contact carrying spring blades (29) extending along and beneath said base, said spring blades of each pair being in broadside overlying spaced relation to each other and extending through and mounted on said tubular mounting member, a pair of elongate resilient contact carrying switch blades (30) respectively interposed between said pairs of spring blades in broadside elongate relationship thereto and extending through and mounted on said mounting member, said switching blades biased into engagement respectively with the contacts carried by corresponding ones of said pairs of spring blades and flexible to overcome the bias and engage contacts carried respectively by corresponding other ones of said pair of spring blades, and a stop member (33b) extending between and in abutment with said two pairs of spring blades and said switching blades to hold said blades against longitudinal movement.

7. A switching device as defined by claim 6, wherein said stop member (33b) is disposed within said tubular mounting member (25).

8. A switching device as defined by claim 7, wherein said stop member (33b) is a pin extending axially transverse to the broadsides of said blades in engagement with recesses in the edges of said blades.

9. A switching device as defined by claim 6 with the addition of a cover, member (37) overlying the lower end of said stop member (33b) and cooperable therewith and with said base (11) to enclose contact carrying portions of said blades, and means (36, 38) cooperable with said stop member (33b) to affix said stop member and said cover member to said base. 

1. A switching device of a tablet type comprising a base (11) having a plurality of projections (14), an axis (15) penetrating through said projections (14) and secured thereby, a plurality of tablets mounted on said base (11) in parallel relationship with each other and each having bores (17) formed in opposing sidewalls thereof and at least one boss (18) formed on the outer surface thereof in coaxial relation with said bores to provide a spacing between two adjacent tablets, operation plates each projecting integrally from the lower surface of each said tablet, and a contract means (13) including spring plates having contacts formed thereon, said contacts being switched by each of said operation plates.
 2. A switching device of a tablet type comprising a base, a tablet pivotally mounted on said base, an actuator projecting from said tablet, a frame of electrically insulating material having a rectangular hollow columnar configuration with open ends and opposite sidewalls, said sidewalls having, respectively, pairs of groups of slits perforated therein which slits are formed into elongated shapes each extending horizontally and are arranged vertically with respect to each group, a cover having a plate member closing one of said open ends and an internally-threaded hollow cylindrical member disposed substantially on the central part of said plate member, a pair of groups of spring contact plate members operated by said actuator and inserted in said groups of slits in a manner to bridge said opposite sidewalls, the portions of said spring contact plate members which are positioned in said hollow frame being cut off at both side edges thereof to form narrow portions so that a substantially circular opening is formed between said pair of groups of spring contact plate members, the hollow cylindrical member being inserted in said substantially circular opening, a cover plate covering said frame, and two bolts threadably engaged with said internally-threaded hollow cylindrical member, one of said bolts securing the frame to the base and the other of said bolts securing the cover plate to the frame.
 3. A switch device as claimed in claim 2, wherein said open end closed by said plate member has recesses formed therein, and said plate member has projections formed integrally thereof, said projections engaging said recesses.
 4. The switching device as claimed in claim 2, in which said contact means comprises a supporting frame (25) having a closed cross section and including a plurality of pairs of slits (28) formed in two opposing sidewalls thereof, a plurality of groups of spring plates corresponding in number to said tablets, each group including a pair of stationary spring plates (29) and a movable spring plate (30), which respectively penetrate through corresponding pairs of slits in a manner to bridge said opposing sidewalls of said supporting frame.
 5. The switching device as claimed in claim 4, in which both of said stationary spring plates and said movable spring plates are disposed in parallel with said supporting frame and have narrow portions (29a), (30a) formed at side edges thereof within said supporting frame, said narrow portions defining openings between two adjacent groups of slits, and further comprising cylindrical members each inserted into each of said openings, whereby the spring plates are prevented from slipping out of position from said sUpporting frame.
 6. A switching device comprising a horizontal base (11), a tubular mounting member (25) having one end disposed toward the underside of said base, two pairs of elongate laterally positioned contact carrying spring blades (29) extending along and beneath said base, said spring blades of each pair being in broadside overlying spaced relation to each other and extending through and mounted on said tubular mounting member, a pair of elongate resilient contact carrying switch blades (30) respectively interposed between said pairs of spring blades in broadside elongate relationship thereto and extending through and mounted on said mounting member, said switching blades biased into engagement respectively with the contacts carried by corresponding ones of said pairs of spring blades and flexible to overcome the bias and engage contacts carried respectively by corresponding other ones of said pair of spring blades, and a stop member (33b) extending between and in abutment with said two pairs of spring blades and said switching blades to hold said blades against longitudinal movement.
 7. A switching device as defined by claim 6, wherein said stop member (33b) is disposed within said tubular mounting member (25).
 8. A switching device as defined by claim 7, wherein said stop member (33b) is a pin extending axially transverse to the broadsides of said blades in engagement with recesses in the edges of said blades.
 9. A switching device as defined by claim 6 with the addition of a cover member (37) overlying the lower end of said stop member (33b) and cooperable therewith and with said base (11) to enclose contact carrying portions of said blades, and means (36, 38) cooperable with said stop member (33b) to affix said stop member and said cover member to said base. 